If you have a database server and an application server, then move your application on the same machine as your database. That's basically the use case of sqlite server-side. You can easily fit 250TB on rack (or 64tb on an ec2.) That's a lot for non-blob storage: 750KB per us citizen
Who has "an" application server though? Those of us who came up through PHP/Rails/Flask and even much of the modern microservices world were taught to do stateless, probably load-balanced application tiers with shared DB, maybe cache, maybe message queue. Both for scalability and redundancy.
Redundant SQLite is not impossible [0] but it is definitely less mature and well-known than replicated MySQL or Postgres.
